1. Field of the Invention
This invention relates to data processing equipment and is particularly useful for, but not limited in its application to, automatic call recording equipment for recording details of telephone calls to enable the charge for the call to be passed to the correct subscriber's account by an operator.
2. Description of the Prior Art
At present the details for a telephone call connected by an operator are written on a card or slip of paper which is passed to an accounts department for analysis and entry of the charge against the subscriber's account. Clearly the time taken to write the necessary information on the card to enable the charge to be assessed correctly and set against the correct account occupies a substantial proportion of the operator's time and consequently reduces the number of calls with which the operator can deal. Moreover, the entry of the call details by hand is liable to error and incorrect calculation of the charge or even its incorrect allocation. Any mistake of this type results in a loss of goodwill by the Post Office or other body operating the telephone service and could result in a loss of revenue.
It is therefore desirable to provide some form of data processing facility to enable the operator rapidly to enter the details of the call, but the system provided must be extremely reliable because it will be extremely expensive to retain the alternative handwritten system at present employed in addition to providing the data processing facility. It is moreover essential at present to check as far as possible that the operator has entered the correct information into the data processing system, and it is therefore desirable that the system could incorporate some kind of feedback display and any other check to which the information is susceptible.
It is an object of the present invention therefore to provide a data processing system suitable for recording details of telephone calls connected by an operator in which the above requirments have been taken into consideration.
According to the present invention there is provided data processing equipment having a plurality of on-line stations, the equipment including data entry and utilisation means at each station, a plurality of data handling and/or storage units, and a plurality of control units each including storage means for recording in response to the data entry means details of a required data processing operation, each control unit also being capable of generating in response to the recorded details interrogation or instruction signals for the data handling and/or storage units, receiving data from the data handling and/or storage units in response to the interrogation or instruction signals, recording the data, and applying signals to the utilisation means, wherein each control unit is connected to a first number of data entry and display means but has the capability of being connected to a greater number than the first number of data entry and utilisation means, and means is provided associated with a plurality of control units for transferring the connections of the data entry and utilisation means allocated to a first control unit to other control units in the event of breakdown of the first control unit. Each station may be operated by an operator and may include display means for the operator.
Each control unit may be arranged to, when following a sequence of operations correctly, to perform a particular operation within a predetermined interval of time following the last performance of the operation, and may include means to detect when the particular operation is not performed within the predetermined interval. The detecting means may be arranged to reset the control unit to an initial point in a sequence of operations if the particular operation is not performed within a given further period of time. Failure to restore the performance of the particular operation within the predetermined intervals in this way may cause the detecting means to indicate breakdown of the control unit.
Each control unit may include an input buffer store for signals from a group of the data entry and display means allocated to it. The filling of the input buffer store may also be used an an indication of the breakdown of the control unit.
In a typical installation, each control unit has allocated to it 8 data entry and display means but is capable of handling 12 such means. On failure of a control unit, two blocks each of 4 data entry and display means are transferred to two other control units respectively.
The equipment may be used for recording details of manually connected telephone calls in a telephone exchange.